Autologous adipose tissue grafting is widely used in reconstructive plastic surgery for the correction of acquired or inherited morphological defects. In breast surgery, lipomodelling is used for the reconstruction of anatomical structures removed as a result of an operation, such as quadrantectomy or mastectomy, performed to remove a cancerous lesion. Recently, breast lipomodelling has also been used as an effective method of performing mastopexy or additive mastoplastic surgery, thus reducing post-operative problems caused by the use of prostheses.
Experimental evidence has shown that non-uniform distribution of the grafted adipose tissue may lead to post-operative complications, ranging from simple resorption of the grafted tissue (up to 60%) to necrotic tissue formation and the formation of adipose cysts. The onset of these complications is generally correlated with reduced angiogenesis in the grafted tissue, due to its concentration in limited areas of the breast.
Uniformity of distribution of the adipose tissue enables these complications to be reduced, by avoiding undesired accumulations.
At the present time, this problem is mainly overcome by the manual dexterity and sensitivity of the surgeon.
There are some lipomodelling instruments available that are intended to resolve the problem of achieving more accurate tissue grafting. For example, U.S. Pat. No. 7,632,251 and EP 2387962 describe a dispenser device comprising a pistol-like housing, a needle direction control mechanism, a boost mechanism, a quantity control mechanism, and a syringe positioning mechanism, wherein the syringe positioning mechanism is fixed on the pistol and coupled to the rear end of the needle direction control mechanism and has two syringe inlets with at least one syringe inlet joined to them. This device enables the syringe to be orientated with respect to the grip with an injected volume of between 1/30 and 1/240 cc per injection and allows the simultaneous injection of two components without their exposure to the air. This is achieved by means of a special mechanism of the trigger.
U.S. Pat. No. 6,524,250 describes a device for measuring and monitoring changes before, during and after a liposuction procedure, and for assisting in producing symmetrical body contours. The device comprises a remote control and data processing unit, a handheld ultrasound transducer, a monitor, and means for marking anatomical points to be measured. The ultrasound transducer is the essential element for guiding the surgeon in the course of the operation. This patent does not relate to the technical problem tackled by the present invention.
US20090275900 describes a syringe comprising a plunger activating system configured by means of gears to provide a one-way movement of the plunger as the body of the syringe is moved away from or towards the positioning guide.
U.S. Pat. No. 7,632,251 and EP2387962 have two fundamental drawbacks which prevent the described solution from resolving the technical problem of achieving uniform distribution of the grafted adipose tissue. The first and most important of these is the complete lack of control over the orientation and position of the instrument. Thus it is impossible to know where the adipose tissue is grafted, both in terms of direction and in terms of position within the channel created by the insertion of the syringe. The second drawback of the teachings of these patents is the “discretization” of the volume of tissue injected. This prevents the deposition of a continuous quantity of tissue in the direction of grafting, except by modulating this quantity during an individual deposition. Essentially, the prior art outlined above is simply a sophisticated version of an ordinary syringe.
US2009275900 provides control of the deposition of the tissue as a function of the rate of withdrawal of the syringe, but does not provide any feedback on the direction of grafting of the tissue. Furthermore, the proportionality of the volume of grafted tissue with respect to the withdrawal rate is not ensured in absolute terms, but only with respect to the supporting guide of the syringe which is held by the surgeon's hand: therefore, any movement of the hand prevents the accurate control of deposition. Moreover, the connection between the syringe and the guide is provided by fixed gears, which therefore do not allow the deposition of the adipose tissue to be modulated within a single direction of deposition.
Other systems are disclosed in US2012209248 and EP1970094.
As far as the inventors are aware, the devices illustrated in the documents cited above are not in use, and therefore not only do they fail to resolve the technical problem tackled by the invention, the solution of which is still dependent on the manual dexterity of the surgeon, but furthermore they have failed to gain acceptance in the clinical field.
The object of the present invention is to resolve the problems of the prior art, and specifically to ensure the uniform distribution of the adipose tissue during grafting, by means of the device described in the attached claims.